The present invention relates to a manufacturing apparatus and, more particularly, to a manufacturing apparatus which may be effectively applied to an apparatus for assembling a semiconductor device which is capable of preventing dust from adhering to a semiconductor element chip as a workpiece when being assembled.
In an apparatus for manufacturing semiconductor devices such as ICs or LSIs, particularly in so-called post-processes carried out before a fabricated semiconductor element chip is packaged, the element, chip is processed in an exposed state, which fact applicants have found involves the problem of adhesion of dust to the surface of the element chip and to the surfaces of other elements. For example, in a chip bonding process in which an element chip is bonded to a package base, dust adhering to the surface of the package base lowers the reliability in bonding of the chip. Applicants have also found that in a wire bonding process, or a resin molding process (for a plastic molded type package), dust adhering to the surface of an element chip causes a wire bonding failure, or a resin molding failure.
FIG. 4 shows a conventionally used wire bonder. In this type of wire bonder, a wire bonder mechanism 102 is mounted on a lower housing 100 which incorporates various control units 101, such as an electrical control unit, and a wire is connected to a workpiece W (i.e., an element chip secured to a package base) set on a bonding stage 103 in the wire bonder mechanism 102. In addition, fans 104 and filters 105 are provided inside the lower housing 100 so as to circulate air through the inside of the lower housing 100, thereby cooling the control units 101.
In this type of wire bonder, dust is generated as a result of the friction occurring between portions of various machine elements within the wire bonder mechanism (e.g., a cam mechanism) 102, and this dust adheres to the surface of the workpiece W set on the bonding stage 103. Further, the action of the fans 104 for cooling the control units 101 causes a turbulent air flow by which dust generated not only inside but also outside the housing 100 is blown up to adhere to the surface of the workpiece W.
The dust adhering to the surface of the workpiece (chip) W, applicants have found, may cause a wire connection failure at an electrode pad, or adversely effect the bond between the chip and the resin in the resin molding operation carried out as a post-process, resulting in problems such as adversely affecting the moistureproofing of the product.
Similarly, in a resin molding machine shown in FIG. 5, an exhaust duct 112 is connected to the upper side of a housing 110 of a molding mechanism 111, and dust generated in the housing 110 is discharged together with air through the exhaust duct 112. In this type of resin molding machine, due to the positional relationship among the exhaust duct 112 and upper and lower cavity blocks 113 and 114 disposed so as to face each other, a turbulent air flow is easily caused inside the housing 110, and dust is thereby easily blown up, particularly in the area between the upper and lower cavity blocks 113 and 114. In consequence, the dust may adhere to the surface of the workpiece W immediately before a resin molding operation, and, applicants have found, adversely affect the moistureproofing of the product, as described above.
It is known from Japanese Patent Laid-Open No. 162335/1981 to provide a clean bench in a clean room for wafer fabrication processes. However, the reference does not disclose using such clean air equipment during so-called post-processes or assembly stages of semiconductor manufacture.